
public abstract class Nod {
	protected Nod fStang;
	protected Nod fDrept;
	protected double x;
	
	public Nod getFStang(){
		return fStang;
	}
	public void setFStang(Nod fStang){
		this.fStang=fStang;
	}
	public Nod getFDrept(){
		return fDrept;
	}
	public void setFDrept(Nod fDrept){
		this.fDrept=fDrept;
	}
	public double getX(){
		return x;
	}
	public void setX(double x){
		this.x=x;
	}

	
	public abstract double calcul();
	public abstract String derivare();
	public abstract double calculDerivata();
	public abstract String toString();
}
